Label-free Cardiomyocyte Enrichment in Microfabricated Device

A. Hsieh, A. Sofla, M. RadisicUniversity of Toronto, CA

Keywords: Cardiac Tissue Engineering, Microfluidics, Cell Separation

Abstract:

Cardiomyocyte (CM) is the functional conducing cells among fibroblast and endothelial in the myocardium. Myocardial infarction results in cell death and scar formation, compromise heart function, and eventually lead to heart enlargement, and death. Cardiomyocyte sources, being derived from embryonic and induced pluripotent cells with their virtually unlimited sources due to its self-renewal and directed differentiation capacity, serve as promising resources for cardiac tissue engineering applications. With CM surface markers still unknown, intracellular labelling requires cell permeabilization and results in no viable cell, impeding translational studies. Herein, we developed a microfluidic chip integrated with magnetic field at 0.5T to efficiently isolate CMs from heterogeneous cell populations. Cell viability and functionality were preserved up to 50mM oxidant treatment (CFDA/PI, ET = 4.6 V/cm, MCR = 8.2 Hz). Target protein in CM was identified in the absorption spectra at the soret band of 400nm as reported in the literature. Elisa quantification showed the developmental increase of the target protein from neonatal to adult rat (0.11 and 0.73 ×10-14 mole/cell, respectively). Maintenance of CM morphology was studied with comparable anti-cardiac troponin T staining. With the current concentrator outside the channel prototype, CM population was enriched through the magnetic microfluidic device compared to non-treated samples by 30% shown by FACS.